In an endoscopic surgical operation (also referred to as “laparoscopic surgery”), one or a plurality of holes are punctured in the abdomen or the like of a patient, and trocars (cylindrical instruments) are inserted through the holes. Thereafter, a laparoscope (camera) and a plurality of forceps are inserted into the body cavity via the one or more trocars. Grippers for gripping biological tissue, scissors, or blades of an electrosurgical scalpel are mounted to the distal end of the forceps as an end effector.
If the laparoscope and the forceps are inserted into the body cavity, an operator operates the forceps while viewing a state of the inner portion of the abdominal cavity, which is shown on a monitor that is connected to the laparoscope. Since the surgical procedure does not require a laparotomy, the burden on the patient is reduced, which reduces the number of days for postoperative recovery and leaving the hospital. For this reason, the fields that such an operative method can be applied to are expected to expand.
Other than typical forceps that are not provided with joints at distal end portions thereof, as forceps that are inserted through a trocar, forceps referred to as a medical manipulator have been developed that are provided with joints at distal end portions and which can carry out a rolling operation or a tilting operation of an end effector (for example, refer to Japanese Patent No. 4391762). In accordance with such a medical manipulator, a high degree of operational freedom is facilitated in the body cavity, manual procedures are made easy, and thus there are a large number of medical cases to which the medical manipulator may be applied.
Further, with the aim of improving operability and facilitating manipulation, a medical manipulator has been proposed that carries out a portion or all of the operations of a distal end working unit by a drive source (motor) (see, for example, Japanese Laid-Open Patent Publication No. 2008-104854). In this type of medical manipulator, a switch operating member is provided on the handle. When the switch operating member is operated, a drive source is driven corresponding to the operating state of the switch operating member, and a distal end working unit is operated accordingly.